This invention relates to foundry apparatus and more particularly to apparatus for shaking sand-cores out of metal castings. More particularly, this invention is an improvement on the Rotary Acoustic Sand-Core Shakeout which is the subject of United States patent application U.S. Ser. No. 009,308, filed Feb. 5, 1979 in the name of Kenneth J. Pol and assigned to the assignee of the present invention (i.e., hereafter Pol-type).
Cores are typically removed by imparting sufficient vibration to the casting to disintegrate the core and shake the loose sand from the internal intricacies of the casting. Chipping hammers, or the like, have been particularly effective for this purpose, and involves nothing more than clamping the casting to the tool end of the hammer and rapidly striking the other end of the tool with a reciprocating piston-like hammer. One of the disadvantages of using such tools, however, is the noise that it generates. Accordingly, a variety of sound enclosures have been developed for reducing this noise during the shaking out operation and the aforesaid Pol-type is directed to one such enclosure. According to Pol-type arrangements, a plurality of work stations are spaced apart around the circumference of a turntable and encased within an acoustical enclosure which is adapted to rotate with the turntable. Each work station includes an appropriate clamp for holding the casting in place and a percussive or impact-type tool (e.g., chipping hammer) for shaking out the core sand. The rotatable enclosure includes sound absorbing partitions separating the several stations one from the other, but provides an access opening for each station facing outwardly of the turntable for loading and unloading castings. A stationary acoustical enclosure surrounds the rotatable enclosure and is in sliding sound-sealing engagement therewith at all major joints between them to contain the sound generated as much as possible to each station. The stationary enclosure has an access port at the operator's station for loading and unloading castings when it is aligned with the access opening of each station. A sand trap is provided beneath the stations for collecting falling sand and sealing off the undersides of the stations against sound emanations therefrom.
It is an object of the present invention to improve the sand trap system of Pol-type apparatus so that it can continuously automatically purge itself of debris entering the system from the decoring hammers or at least permit ready access to the system for manual removal of such debris. This and other objects and advantages of the present invention will become more readily apparent from the description thereof which follows.